Schiff&#39;s bases derived from cyclanic amines and method for using same as agricultural pesticides

ABSTRACT

NEW SCHIFF&#39;&#39;S BASES HAVING THE GENERAL FORMULA   2,4-DI(X-),6-(R-N=CH-)PHENOL   WHEREIN X IS HALOGEN , AND R IS A CYCLOALIPHATIC OR TETRAHYDRONAPHTYL RADICAL, WHICH MAY BE SUBSTITUTED BY ONE OR MORE RADICALS SUCH AS OH, HALOGEN, ALKYL, HALOGENATED ALKYL; AND THE SALTS AND METAL CHELATES THEREOF; AND THEIR USE AS FUNGICIDES FOR AGRICULTURAL USE.

United States Patent 1m. 01. C07c 119/00 US. Cl. 260-4293 19 Claims ABSTRACT OF THE DISCLOSURE New Schiffs bases having the general formula OH=NR )C OH wherein X is halogen, and R is a cycloaliphatic or tetrahydronaphthyl radical, which may be substituted by one or more radicals such as OH, halogen, alkyl, halogenated alkyl; and the salts and metal chelates thereof; and their use as fungicides for agricultural use.

The present invention relates to new Schiifs bases derived from halosalicylic aldehydes, and to the use of such products as agricultural pesticides, in particular as fungicides.

The new products according to the invention have the general formula CH=NR i i 6H wherein X is halogen, and R is a cycloaliphatic or tetrahydronaphthyl radical, which may be substituted by one or more radicals such as OH, halogen, alkyl, halogenated alkyl.

The present invention relates also to the chelates of the compounds having the Formula 1, with divalent metals such as copper, zinc, iron, manganese, cobalt, and the like. Lastly, it relates to the organic salts of the esters of the compounds having the Formula 1, in particular to the acetates thereof.

The Schiffs bases are produced by condensing a dihalogenated salicylic aldehyde on a primary amine having the formula H NR, according to one of the following methods:

(A) Condensation is carried out at ordinary temperature, by mixing equimolecular amounts of aldehyde and amine, which have been previously dissolved in a suitable solvent such as methanol. The solution turns yellow immediately, and then, after a period of time ranging from a few seconds to several hours, the derivative crystallizes. The precipitate is drained, and then re-crystallized in a solvent such as ethanol, or methylketone.

(B) The above equimolecular mixture of aldehyde and amine is heated in toluene, with azeotropic removal of the water formed during the reaction. When the derivative cannot be crystallized by cooling, the solvent is 3,632,618 Patented Jan. 4, 1972 allowed to evaporate under diminished pressure, and the residue re-crystallizes in water or in an organic solvent such as methanol.

The following compounds were prepared according to either of the above-mentioned methods:

Melting Yield, point R percent C Oyelopentyl 82 60 Cyclohexyl 85 Oyclopentyl 91 80 Tetrahydro 1-2-3-4 naphthy 90 126 0 Hydroxycyclohexyl 48. 5 169 Cyclohexyl. 77 do 66 66 o-Hydroxycyclohexyl 74 194 Tetrahydro 1-2-3-4 nap thyl-1 92 do 51 111 o-Hydroxycycl0hexyl 71 184 o-ChlorocyclohexyL- 88 103 Tetrahydro 1-2-3-4 naphthyl-Z. 86 138 o 97 144 The organic salts of the esters of Schiifs bases are produced by allowing the anhydride of the organic acid to react with the corresponding Schiifs base.

By way of example, one part of Schifls base is poured into 10 parts of acetic anhydride containing 1% pyridine. The mixture is allowed to stand for 24 hours, at ordinary temperature. The excess acetic anhydride is then removed at reduced pressure, and the acetate of the O-acetylated derivative precipitates, and is re-crystallized in ethanol.

The following products were obtained by said method:

l -0H=N@, ornoo OH M.P. 141o. Yie1d=55% l (BCOCH (J (SCOOH;

PREPARING THE CHELATES The chelates are produced by allowing a soluble metal salt to react with the Schitfs base.

By was of example, a concentrated aqueous solution containing 0.1 mole of metal acetate, is poured at ordinary temperature into an alcoholic solution containing 0.2 mole of Schitfs base. The chelate precipitates immediately. After being drained, and then washed with water and ethanol, it re-crystallizes as a rule in ethanol, methylethylketone, dimethylformamide, or a mixture of said solvents. With this method, chelates are produced, which have the general formula:

. wherein X and R have the same meanings as hereinabove,

and Me is a divalent metal.

The following compounds may be mentioned in particular:

Melting Yield, point,

X R Me percent C.

Cyclopentyl Cu 218 Oyclohexyl Cu 244 C1 .-d Zn 238 The fungicidal action of the above compounds was determined by tests on a number of plant parasitic fungi.

Obviously, the fungi in the tests described hereinafter are only mentioned by way of example, to illustrate the fungicidal activity of the compounds according to the invention, and do not represent the whole range of ac tivity of said compounds.

(I) TESTS ON LIVING PLANTS the fungicidal action of which Was studied by Smith and Read, (Annals of Applied Biology 1961, 49, 242-245).

(a) Test relating to corn-mildew In this test, the compounds Nos. 1, 3, 6, 7, and 8 obtained a mark 4 for protection against Erisyphe graminis, which is the cause of corn-mildew. Under the same conditions, the salicylidene aniline of Smith and Read only obtains a mark 2.

(b) Test relating to Alternaria solani (tomatoes) In this test, the compounds Nos. 3 and 11 obtained a mark 4, whereas the product studied by Smith and Read obtained only a mark 3.

(c) Test relating to celery septoriasis In this test, the compounds 1, 2, 3, 5, 6, 7, 8, 9 and 11 provided a total protection (mark 4) against Septoria apiz', whereas the product studied by Smith and Read only obtained a mark 3.

(II) Tests on vine leaves The treatment is effected by means of the same wettable, powder (diluted so as its concentration is 0.01 g./l. of active material) on a vine-leaf still alive, which is then infected with Plasmopara viticola. In this test, the compounds Nos. 1, 3, 5, 7 and 9 prevented totally the growth of said parasitic fungus.

With a dose ten times smaller, the protection provided by compound No. 1 was still total. In this test, a dose ten times higher of the product of Smith and Read is required to obtain the same extent of protection.

With a view to using practically the compounds according to the invention, said compounds should be formulated according to the technics conventionally used in the pesticide industry. Thus, they may be used as powders to be sprinkled, wettable powders, solutions, direct or 4 reversed emulsions of water in oil, or oil in water, and the like.

These various types of formulations require normally the addition of inert carriers, such as clays, talc, or the like, solvents such as water or organic solvents, as well as various adjuvants adapted to further the use and physical properties of the compositions produced. Such adjuvants many be emulsifying agents, and/or anticaking agents, and/or wetting agents, and/ or sticking agents, and the like.

What we claim is:

1. A Schiffs base having the formula:

wherein X is halogen and R is cyclopentyl, cyclohexyl or tetrahydronaphthyl, the said cyclohexyl may be substituted in ortho position by OH or C1; or the acetate salt of the o-acetylated derivative or the metal chelate thereof wherein the metal is selected from the group consisting of copper, zinc, iron, manganese and cobalt.

2. Compounds according to claim 1 which have the general formula wherein X and R are according to claim 1 and Me is said metal.

3. A compound in accordance with claim 1 wherein X is iodine and R is cyclopentyl.

4. A compound in accordance with claim 1 wherein X is bromine and R is cyclohexyl.

5. A compound in accordance with claim 1 wherein X is Cl and R is cyclopentyl.

6. A compound in accordance with claim 1 wherein X is Br and R is tetrahydro-1-2-3-4 naphthyl-l.

7. A compound in accordance with claim 1 wherein X is Br and R is o-hydroxycyclohexyl.

8. A compound in accordance with claim 1 wherein X is I and R is cyclohexyl.

9. A compound in accordance with claim 1 wherein X is Cl and R is cyclohexyl.

10. A compound in accordance with claim 1 wherein X is I and R is o-hydroxycyclohexyl.

11. A compound in accordance with claim 1 wherein X is I and R is tetrahydro 1-2-3-4 naphthyl-l.

12. A compound in accordance with claim 1 wherein X is Cl and R is tetrahydro 1-2-3-4 naphthyl-l.

13. A compound in accordance with claim 1 wherein X is C1 and R is o-hydroxycyclohexyl.

14. A compound in accordance with claim 1 wherein X is I and R is tetrahydro 1-2-3-4 naphthyl-Z.

15. A compound in accordance with claim 1 wherein X is Cl and R is tetrahydro 1-2-3-4 naphthyl-2.

16. A compound in accordance with claim 2 wherein X is Br; R is cyclopentyl and Me is Cu.

5 17. A compound in accordance with claim 2 wherein X 3,253,022 5/ 1966 Linder et a1. 2605 18 is C1; R is cyclohexyl and Me is Cu. 3,357,883 12/1967 Pillon et a1. 16731 18. A compound in accordance with claim 2 wherein X is Cl; R is cyclohexyl and Me is Co. LEON ZITVER, Primary Examiner 19. A compound in accordance with claim 2 wherein X 5 SCHWARTZ Assistant Examiner is C1; R is cyclohexyl and Me is Zn.

US. Cl. X.R. References Cited 260 429 C 4381 439 R 479 R 566 F- 424 287 289 UNITED STATES PATENTS 10 95, 31 1, 325 3,090,720 5/1963 Kenaga 16731 3,153,093 10/1964 Horrom et a1 260-570.5 

